Process of reducing iron oxids.



2Q any of the ordinary ores .such as the sand ores of the St. Lawrence and'New Zealand, and I find that the associ I UNITED STALTES.

PATENT OFFICE.

success or nnn'iiome rao'noxrns. n

To all whom it may concern- J "t Be it known that I, Henson W Lssrn'a citizefo'l theUnited States, residing'at Cleveland, in the county ofCiiyahoga and'State of Ohio, have invented a'certairi nods and useful Improvement in'the Process of Reduc-.

ing" Iron oziids of which thefollowing isa full, clear,

' id xact description.

' My invention relates to the reducing-of iron oxide in connectionwith finely divided cast or pig iron, either into'finished steel or into a partially refined condition suitable for themakingof castings, or finished iron or I 'steelhy further treatment.

Y-comminutejd oxid of iron, such-as iron sand or scale, and mix the-same with finely divided cast or pig iron and a'carbonaceous material as coke. The several in-, gredients may if preferred, receive their final comminu'tion during the mixing gether during the mixing.

'Incafryingout my invention -1 use finely ground or process by being ground to- The iron oxidwhich I employ may be obtained from ation oisuch substances as titanium oXid does not interiere'with the process. vThe essential thing is that the iron oxid shallbe in a finely-divided condition in the mixture. I

=- Thecast or pig iron may beobtained iroinany supconvenient, but itis necessary that this addition 1 'tothe mixture shall be distinctly ofrthat quality of Y3? I guished from the-ordinary run of scrap, wrought iron iron commonly designatedlas cast 'or'pigiron, as distin- 3 or steel .sinceit is important that it contain a high percentage of nletalloids or oxidizableunetals, such as manganese, capable of uniting-with the oxygen of the ore.

The free carbonaceous material forming part of the I mixture is preferably in the form of ordinary coke and is finely ground, a's are the other portions of the charge mixture. l

In addition to the abovev mentioned ingredients I .find it advantageons in some cases to' add 'a readily combustible material, such as sawdust or crushed bituminousfcoal which shall 'be'consumed during the early stages of the. smeltingoperati'on and thus leave the mass porous. so that the smelting may proceed with greater'rapidity. The combustion of the sawdust vor bituminous ,coal is not, of course, perfect under such conditionsand has the, effect of coating the-particles of iron oxid with carbon, and it may be that this action adds somewhat to the effectiveness of the mixture.

. I usually addfluxes of the ordinary kirid, as lime and huorspar, variedto suit the different grades of ore.-

Specification of Letters Patent. Application filed December '28 1906. aerial-No. 349,812.

When it is desired that the mixture iron. p v .Thisrernarkably simple and effective method-of smelting the finely di'yided o xi'ds of iron, which it has "hitherto been thought impossible to handle owing to PatentedJuly 23.1901

I r It is however cugomary to add such flurreato smelting mixtures and I ture of my mixture, I

in the form of lumps. or: briquets," any oiithe prdinaiy binders,- such as pitcher oil, may be employed.

6 not claim any no /shy for this fea- V n be handled":

The mixture'described' consisting of 'iron ox'id, carbonaceous rnaterialaiid pig cast iron high in metal-" loidsi'or oxidizable metals such as manganese, is charged directly upon the hearth bf a metallurgical or rege'nerative gas furnace, such as is commonlyused in: the -ma nufacture of, open hearth steel; The heat; is then supplied the ordinary way and in thecourise oi a-few hours it is found that theentire quantity of iron added as iron oxid is reduced to metallic iorm,'forminga bath with the inetallic iron added in the forrrvofpi g or cast the fact that they are too light for blast furnacesmelt- 'ing, is best explained as follows. The action'of the pig or cast iron in the finely-divided'niixture is two-fold-in its character:-First and primarily the pig iron contains a'high percentage of mctallbids and,

i generally, manganese, which elements, upon the fusion of the iron, arepr'esented to the oriid in the most intimate and effectivel condition'possible 'and' become active and ready reducing agents; Secondly,

the fused pig iron seems to act simultaneously as a' solvent'for some of the free carbon and as an enveloping co'atfor the individual particles of oxid, thus. bring. ing such dissolved carbon into intimate association withthe oxid to supplement the effect of the metalloids already contained in the pigiiron, 'in their reducing action 'jThe free carbonaceous material should be pres-' ent in suflicient quantity to insure, the proper carburization of the smelte'd metal so as to maintain it in a, fusible condition and also suiiicient 'to protect the mix:

ture against atmospheric oxidation. v The presentationrof the reducing agents to the oxids to certain ineyitable losses, be brought to the theoret I icallimits necessary forsimplereduction of theoxids, 'the quantity of cast-iron necessary for practical work.

ofiron through the inediurn of the fusedirnetal is so .effective that although. the proportions'niay not, owing is so small that it need never be. greaterthan the weight- I V ofthe oxidiunder treatment. and may be considerably; less, successful results having been obtained where J the cast-iron was not more than one fourthrthe weight j of the iron oxid. The quantity of free carbonaceous material used'tuns from about one sixth to one tenth,

by weighl' 'of thefiron oxid, being controlled by the I conditions undei which the mixture is to be smelted. Iii-practice I have found. the following proportions to produce n, satisfactory mixture for smelting:

Miktnro Mixture bglIxtnl-e 4 No No. 2. o. 8.

Ore 10.00 12.00#- 1800* 1 Cast-iron 10.00 0.00 7.00 -carbon...... 2.00 2100 2.00 Limestone Q 50 v .25- Fluo 'sper... ;50 .2'5 .25 Sawdust. .50 .50 .50

These proportions may, of conrse, be vili ied within ob-- vious'limits, so 'lon g'as the. essential characteiistics outlined in the preceding portion oi the specification obtain. r

After'the reduction of the oxid and the fusion takesplace, the 'refining operation may be carried onto produce finished stejel, aftein'which the bothmay be drown off in the usn 'zil Way and cast into ingots or other desired. form, the metal may be tapped off in a partially re- .fixiejd condition giving a product suitable ior tlie menu iactnieof costings, or-finished iron 'or steel by further "-treotmexii. The unique feature of my mixture and procedure is the utilization of the. nietelloids and oxidizable metalss,u ch as inangonese,'in the cast or pig iron, to

effect the 'l eduction of the finely divided iron oi oxid.

the presence of two witnesses; I

The action and effectiveness of "cast iron, in this,

process is ahove'ontlined and the function ofthe can bonaceous material in assisting'the action is made clear,

and I have endeavored to'clearly distingi ish the some f 'om the old cementation pljoc'esses an iprior methotiis in which iron oxid was used simply as'a refining or deem .buiizing agent. In'none of these i3 fonnd the idea'of source of the iron using finely divided iron 'oxid ss'th bath in a smelting operation.

-' Having thus described my invention; Ijclaiinr 1. The method of i-edncing lpon oxids, consisting in mixihg finely divided iron high in inetalioids -v $ith finely di,

vided iron onid. and finely divided ,corbonaceous m'ate1jal, charging themixture upon the hearti 'of a tiirnao, and

melting down scrlbed w and reflningthe :saxne; snbistsntially as de- 2. The method-0i reducing i'i'on o'xids, consisting in 'in'ti-,

matoly mixing finely .diyjdedicast iron with flnly gronndp. oxid 0t iron. carbonaceous mate 'iols, and flinging mntei-izilsl, charging the some directly-upon the health of a Iur-' nace, and than melting down and refining the some; Snb stantially'as descrihefl.

3. The method of reducing 113011 oxids eon sist;ing in charging upon the heiuth of a-furnnoe amixtuye-oroxid of iron, finely divided cast iron; and finely granny! carbonaceous mt\.t0l'i fli and mining materials, substantially in the proportions above speeifi'ed, andthon melting down am} re.

,iiningthe change; substantially as described:

in testimony whereofi. I hereunto aflix-m y sign'atnre in -1-1oimcn vw; LAsH,

- Witnesses J. M. Wooow'ssn,

E. B. Ginc'nn sn v 

